Wow, another solid puzzle adventure! I haven't beaten it yet because damn, some of these puzzles are really cryptic, but I love the challenge and the creativity in all of them!
I gotta admit that I had a bit of a rough start: I was just sailing in random directions trying to find islands and getting frustrated at what I was supposed to do, not realizing that the island right at the start had already changed to something new. But once I got the gist of doing sequences to change what the starting island is, I easily got addicted in collecting more and more clues and solving these puzzles.
If I were to have any complaints so far, it might be that while figuring out that you could changes docks at that island by approaching it in different ways to access the caves made me feel pretty clever, having to go back and forth to the boat to access the puzzle caves one-by-one was quite tedious and I much would've preferred if I could just walk to them, at least by unlocking a shortcut like the bridge for the castle, haha.
Reminds me a lot of 'Lost in Firefly Forest' which was another one of my favorites: keep up the good work!